Revert of Update mojo sdk to rev 8af2ccff2eee4bfca1043015abee30482a030b30

third_party/mojo/src/mojo/public/go/system/message_pipe.go

Index: third_party/mojo/src/mojo/public/go/system/message_pipe.go
diff --git a/third_party/mojo/src/mojo/public/go/system/message_pipe.go b/third_party/mojo/src/mojo/public/go/system/message_pipe.go
index 79f0ae962439a358cd3c1a69004bb1d9f8b49cf2..3188ecfe256fc6f79489a6d8ae1a9efa6a81d47e 100644
--- a/third_party/mojo/src/mojo/public/go/system/message_pipe.go
+++ b/third_party/mojo/src/mojo/public/go/system/message_pipe.go
@@ -32,9 +32,6 @@
 }
 
 func (h *messagePipe) ReadMessage(flags MojoReadMessageFlags) (MojoResult, []byte, []UntypedHandle) {
-	h.core.mu.Lock()
-	defer h.core.mu.Unlock()
-
 	cParams := C.MallocReadMessageParams()
 	defer C.FreeReadMessageParams(cParams)
 	*cParams.num_bytes = 0
@@ -55,15 +52,12 @@
 	cHandles := *(*[]MojoHandle)(newUnsafeSlice(unsafe.Pointer(cArrays.handles), handlesLen))
 	handles := []UntypedHandle{}
 	for i := 0; i < handlesLen; i++ {
-		handles = append(handles, h.core.AcquireNativeHandle(cHandles[i]))
+		handles = append(handles, &untypedHandleImpl{baseHandle{cHandles[i]}})
 	}
 	return MojoResult(result), bytes, handles
 }
 
 func (h *messagePipe) WriteMessage(bytes []byte, handles []UntypedHandle, flags MojoWriteMessageFlags) MojoResult {
-	h.core.mu.Lock()
-	defer h.core.mu.Unlock()
-
 	cArrays := C.MallocMessageArrays(C.uint32_t(len(bytes)), C.uint32_t(len(handles)))
 	defer C.FreeMessageArrays(cArrays)
 	cBytes := *(*[]byte)(newUnsafeSlice(unsafe.Pointer(cArrays.bytes), len(bytes)))